Rapid and in-situ chemical vapor analysis provides vital information in many fields, such as environmental monitoring and protection, homeland security and biochemical warfare agent detection, industrial process control and safety monitoring, and healthcare fields, among others. However, most gas sensors lack sensing selectivity, significantly limiting their ability to identify and quantify different volatile organic compounds (VOCs) from real-world samples. In contrast, gas chromatography is a powerful analytical technology and is regarded as a standard method in gas analysis. Gas chromatography relies on the interaction between gas molecules and a polymer coating on gas chromatography columns to separate different molecules and to identify them by their unique retention times. Although current bench-top gas chromatography systems are able to detect hundreds of vapor compounds, they are bulky, power intensive, and usually placed in a centralized lab with dedicated personnel. These bench-top systems are not especially suitable for in-the-field applications.
The drawings illustrate only example embodiments and are therefore not to be considered limiting of the scope of the embodiments described herein, as other embodiments are within the scope of this disclosure. The elements and features shown in the drawings are not necessarily drawn to scale, emphasis instead being placed upon clearly illustrating the principles of the embodiments. Additionally, certain dimensions or positionings may be exaggerated to help visually convey certain principles. In the drawings, similar reference numerals between figures designate like or corresponding, but not necessarily the same, elements.